Arthroscopic Anatomic ACL Primary Repair Restores Anterior Tibial Translation Intraoperatively at Time Zero with no Additional Effect of Suture Augmentation.

PURPOSE: To intraoperatively evaluate the ability of Anterior Cruciate Ligament Primary Repair (ACLPR) to restore anterior-tibial translation (ATT) at time-zero, and to assess the influence of additional suture augmentation (SA) on ATT.

METHODS: Patients with proximal ACL tears undergoing arthroscopic ACLPR with dual suture anchor fixation (ACLPR-SA) were included in this time-zero clinical study. Lachmeter laxity measurements were taken to evaluate ATT stability preoperatively in the office (T0) as a standardized diagnostic tool, preoperatively under anesthesia (T1), at time-zero intraoperatively after ACLPR but prior to SA fixation (T2) and following SA fixation (T3).

RESULTS: A total of 27 patients (35.1 ±12.0 years) with proximal ACL tears and significant preoperative (T0) ATT side-to-side difference (SSD) (mean ±SD, 4.1 ±1.5mm) were evaluated. ACLPR was shown to restore ATT SSD at time-zero (mean ±SD, 0.2 ±1.1mm), as a significant reduction in ATT SSD (mean difference ±SE, -4.7 ±.21 mm; p < .001) was achieved comparing pre- and intraoperative measurements after separate refixation of both ACL bundles with suture anchors. Additional SA fixation did not further decrease ATT, comparing measurements of the ipsilateral leg (IL) after ACL refixation and after fixation of the SA (mean difference ±SD, 0.03 ±0.22 mm; p =.496).

CONCLUSION: ACLPR with dual suture anchor fixation restores time-zero ATT in adults with proximal ACL tears. Additional suture augmentation fixated in full knee extension does not further decrease ATT.

CLINICAL RELEVANCE: This study provides important information about the effectiveness of ACL primary repair in restoring anterior tibial translation. Suture augmentation with the knee fixed in full knee extension does not further decrease ATT, therefore augmentation may not overconstraint the knee or stress shield the repaired ACL.